Pneumatic piano-player.



W. G. MAOARTHUR. PNEUMATIC PIANO PLAYER.

I APPLIOATION FILED AUG.13, 1910. 1,003,279. Patented Sept. 12,1911.

2 SHEETS-SHEET 1.

. o v o WITNESSES: 1

ATTORNEYS W. G. MAOARTHUR.

PNEUMATIC PIANO PLAYER.

APPLICATION FILED AUG. 13, 1910.

1, 3,279, Patented Sept-12,1911.

2 SHEBTSSHEET Z. .1: .53.

IN [/5 IV TOR ATTORNEYS -QWIL IAM GIFFGRD MAGABTHUR, or NEW YORK, N. i

ASSKGNOR OF ONE-HALE T L'OUIS MEYER, QF NEVJ' YDRK, N. .Y.

PNEUMATIC PIANO-PLAYER.

Application filed August 13 To all whom it may concern:

Be it known that 1, WILLIAM G. Mac- ARTHUR, a citizen of the United States, and a resident of the city of New York, borough of the Bronx, in the county and State oi New York, have invented a new and Tmproved Pneumatic Piano-Player, of which the following is a full, clear, and exact description.

This invention relates to a new and improved piano-player of the pneumatic type. An object ofthis invention is to provide a device which will be simple in construction, inexpensive to manufacture, strong, durable 5 and both quick and. positive in its action.

A- further object of this invention to provide a piano playing attachment in which the pneumatic portion is attached directly to the keys, whereby a great saving in space 22; and more positive and sensitive movement is obtained. 1 These and further objects, together with the construction and combination ofmarts, will be more fully described hereinafter and particularly set forth in the claims.

Reference is to be had to the accompany ing drawings forming a part of this sp' cation, in which similar char-act f reference indicate corresponding parts views, and in which- Figure 1 is a vertical section tl piano with my attachment thereon an enlarged section through one of the keys and the pneumatic connected thereto, show-- ing the key in its raised position; Fig. is a view similar to Fig. 2. showing the key in its depressed position; F 1 is a section along the line 44 of Fig. 8, showing a plurality of keys;'Fig. 5 is a vertical section on the line 5-5 of Fig. 3; and Fig. 6 is a horizontal section on the line 6-6 of Fig. 3,. looking in the direction of the arrow.

Referring more particularly to the separate parts of the device, 1 indicates the casing of the piano, which is provided with'the usual strings 2, which are adapted to be sounded by hammers 3, forming a part of the piano action 1, which may be of any suitable character. The lowermost member of the piano action 4, indicated at 5 in each case, rests on one of a plurality of keys 6, which may be of any suitable form, preferably pivoted intermediate their ends, as indicated at 7. The weight of the action and the spring tension thereon normally holds Specification of "Letters Patent. Patented Sept, 12, 1911,

, 1910. Serial No. 576,989.

the rear ends of the keys 6 depressed and the forward ends raised, as is usual.

' Extending transversely of the keys 6, and

supported by the casing 1 in any well known manner, there is provided an air-box 7, which is connected in any suitable manner, as by means of atube 8,to a suitable source of suction, such as that indicated by the bellows 9, which may be operated in any suitable maner, as for example by the pedals 10.

For each or"- the keys 6, there is provided an opening 11 in the top of the air-box 7. For eachof theopenings 11 and each of the keys 6, there is provided a casing 12, each of which has an opening 13 extending in alinement with the openings 11. The casing 12 is divided into two compartments by means of a partition 14:. These compartments are indicated by means of the numerals 15 and 16. The former may be termed the vacuum compartment, and the latter, the atmospheric compartment, inasmuch as the former is connected to the vacuum air-box 7' and inasmuch as the latter is connected to the atmosphere by -means of a passage 17 and passages 18, the latter letting out of the side of the casing 12 to tlu atmospl'iere.

The top of each of the casings 12 and the bottom of each of the keys 6 foam the top and bottom. walls of a pneumatic chamber 23, the side walls of which are formed of an accordion-plaited flexible member 19, formed of any suitable impervious material, such as rubber sheeting.

For the purpose of securing each of the members 19 to each of the keys 6, the keys are cut out at 20 and 21 to form slight grooves in which the edges of the flexible members 19 are inserted and secured. The chamber 23, which is formed bet-ween the bottom of the key and the top of the casing, may be termed a pneumatic, and is connected in each case by amopening 22, to the atmospheric compartmentlG. When any one of the keys 6 is in" its normal raised position, the compartmentwlti is connected to the atiosphere, and therefore the chamber 23; is also connected to the atmosphere.

In order to connect the chamber 28 and the compartment 1i to the vacuum chamber 15, and thus to the source of suction, there is provided in the partition 14 an opening 24, which forms a means of communication between the compartments 15 and 16, This opening 24 is normally closed by means of a single valve 25, which extends through and is free to move in the opening 24: and has an upper flange or head 26, which is adapted to close tightly in the surrounding surface of the opening when the valve is in its lowermost position. The valve 25 rests at its lower end on a flexible diaphragm 27, which may be of any suitable form and material, and covers a cavity 28 in the casing 12. This cavity 28 is connected by means of a passage 29 to a tube 30. There is one of these tubes 30 fol-each of the casings 12 and each of the keys (hand they are connected at their opposite ends to a tracker 31 provided with suitable openings 32. For the purpose of operating the device, these openings 32 are normally closed tubes 30 and thus come under the diaphragm 27. When atmospheric pressure has been admitted beneath the diaphragm 27, in view of the lower pressure on the top of the diaphragm 27 it will overcome the weight of the valve 25, raising it, so that its head 26 shuts oil the opening of the passage 17,

cutting off communication between the com partment 1.6, the chamber 23 and outside atmosphere, and sinmltaneously opening communication between the vacuum compartment 15 and both the con'ipartn'ient 16 and the chamber 23. When this has been done, the chamber 23 will be submitted to the suction or negative pressure of the vacuum air-box 7, and the key 6 will be drawn down and caused to actuate the piano action 4.

For the purpose of drawing out the air in the cavity 28 and the tube 30 when the opening 32 corresponding thereto has been again covered by the music sheet. 33, there is provided a bleed passage 31-, which connects the passage 29 to the vacuum compartment 15. Vhen the negative pressure on both sides of the diaphragm 27 has been equalized, the weight of the valve 25, plus the atmospheric pressure on its head, will cause the valve to force down the diaphragm 27, seating its head around the opening 2st, thereby simultaneously opening the chamber 23 to atmospheric pressure and cutting it off from the source of suction.

The operation of thedevice will be readily understood when taken in connection with the above description.

Vhen it is desired to play the piano, a reel having a music sheet 33 with perforations therein corresponding to the notes of the piece which is to be played, is placed in coiiperative relation with the tracker 31..

in contact with the strings 2, thereby sound- At the same timethe air-box 7 is placed under a negative pressure or vacuum by means of a suitaldc device, such as the bellows 9, operated by any suitable force, such as the pedals 10. \Vhen an opening in the sheet 23 comes in opposition to an opening in the tracker 31, the atmospheric pressure admitted to the under side of the corresponding diaphragm 27, so that the valve is raised, cutting off communication of the compartment 16 and the chamber 23 with the air,- and. simultaneously opening up communication between the vacuum box 7, the vacuum compartment 15 and the compartment 16 and the chamber 23, so that the member 19 is collapsed, and the key- 6 drawn down, causing the opposite end of the key to be raised, and actuating the action 4., so that the hammer 3 comes ing the strings. When the opening in the music sheet 33 has passed out of alineme-nt with the opening 32 in the tracker 31, the atmosphere will be cut oft from communication with the under side of the diaphragm 27, and the air in the cavity 28, the passage 29 and the tube '30 will be sucked out through the bleed passage 34-, so that the valve 25 will be forced down by the atmospheric pressure on its head and by its 'weight, so as to close'the opening 24: thus shutting ofl communication between the sourceof vacuum and the chamber 23, and simultaneously opening communication be tween the atmosphere and. the chamber 23, 100,

to the keys, and thus also increase the positivencss of the action.

Vhilc I have shown one embodiment of my invention, I do not wish to be limited to the specific details thereof, but desire to i be protected in various changes, modifications and alterations which I may make within the scope of the appended claims.

Having thus described my invention, I no claim as new and desire to secure by Letters Patent I 1. In a piano player, the combination with a plurality of keys arranged in juxtaposition, oi a series comprising a plurality of air compartments and an air chamber located subjacent each of said keys in superposed relation, the bottom wall of each of said keys forming a wall of said chamber, the top wall of one of said compartu'lenls 13/ located subjacent each of said keys in superposed relation, the bot-tom Wall of each of said keys forming a wall of said chamber, the top Wall of one of said compartments forming a wall of said chamber, a passage between said compartments, a valve control ling said passage, a suction-operated diaphragm for operating said valve, and a common suction air-box extending transversely beneath said keys and connected to the bottom compartment in each of said series.

In testimony whereof I have signed my name to this specification 1n the presence of two subscribing Witnesses.

WILLIAM GIFFORD MAGARTHUR.

lV-itnesses IRENE S. FLAM, DAVID FLAM.

Copies of this-patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. GQ 

